[Bug other/63155] [4.9/5 Regression] memory hog

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63155

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
So the issue is that the setjmp argument needs two temporaries:

  D.2832 = Unity.CurrentAbortFrame;
  D.2833 = &Unity.AbortFrame[D.2832];

  <bb 18>:
  D.2834 = _setjmp (D.2833);

and the EH edge going into the _setjmp call has to merge those through
the abnormal dispatcher.  And that way it receives all of them.  Hmm.

Huh.  Without the abnormal dispatcher they should just get default defs
everywhere (but still many PHI nodes).  Maybe that would be more light-weight.